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Please critique my image -- ab file and stack attached

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#1 42itous1

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Posted 26 October 2020 - 01:50 PM

This is 3.3 hours widefield.

 

sv70t w/reducer

CGEM

dithered every 3 frames

in PI:

 

Wbpp

dcrop

pcc

ezdenoise

ezsoftstretch

ltgb combo with chroma nr

curves

sat

scnr green

ez star reduction

 

 

I am ready to try to progress a little more--but don't really see the problem areas in my images as well as I should--so please tell me what you might do to tweak the image.  No need to be kind--give it to me straight , Doctor smile.gif  This right now seems about the best I can do.

 

 

 

 

get.jpg?insecure

 

XISF stack attached if you want to play with it

 

https://www.dropbox....4E0toziGcDspv22

 

FITS file

 

https://www.dropbox....cUzo6mBi7gpItu5


Edited by 42itous1, 26 October 2020 - 02:50 PM.

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#2 imtl

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Posted 26 October 2020 - 02:21 PM

Just a personal opinion, if you really want to advance skills, learn first how to avoid using the general scripts (WBPP and EZsuit) and do it yourself. It will take more time to process for sure, but you will have much better understanding and control over what is happening in your image.

 

Its a great image by the way. Probably benefit more integration as usual.


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#3 42itous1

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Posted 26 October 2020 - 02:46 PM

Thanks, Eyal

 

That is the kind of thing I'm looking for.

 

Actually I have processed manually, and have used various methods of noise reduction--Jon Rista's, Light Vortex and Cfoster's methods of manual preprocessing.  I've used Arcsineh stretch and masked stretch and some plain HT streches. And I belong to IP4AP (Keller's site)

The thing is, using the Wbpp, EZ suite with ABE and PCC--looks better to me. 

 

But that is also what I would like to know--is this image overcooked?

 

Could I bring out more with a different stretch?

 

is the noise reduction creating artifacts?

 

Is the contrast wrong?

 

would more integration be better?  (you answered that for me) :)



#4 imtl

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Posted 26 October 2020 - 03:05 PM

Thanks, Eyal

 

That is the kind of thing I'm looking for.

 

Actually I have processed manually, and have used various methods of noise reduction--Jon Rista's, Light Vortex and Cfoster's methods of manual preprocessing.  I've used Arcsineh stretch and masked stretch and some plain HT streches. And I belong to IP4AP (Keller's site)

The thing is, using the Wbpp, EZ suite with ABE and PCC--looks better to me. 

 

But that is also what I would like to know--is this image overcooked?

 

Could I bring out more with a different stretch?

 

is the noise reduction creating artifacts?

 

Is the contrast wrong?

 

would more integration be better?  (you answered that for me) smile.gif

I don't think your image is overcooked. I think its a really nice image. You got noise in it which is fine. It is what it is. Its also "only" 3.3 hours integration (OSC?). I don't know your sky pollution situation but it looks really nice.

 

You will benefit by reducing your stars to bring out more of the nebulosity. Your star field is dominating your image. Maybe you wanted it like that?

 

I didn't see any artifacts that pop out, I can take a closer look later for sure.

 

Regarding different stretch and contrast. This again is your choice. What do you want to emphasize in your image?



#5 42itous1

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Posted 26 October 2020 - 03:19 PM

I don't think your image is overcooked. I think its a really nice image. You got noise in it which is fine. It is what it is. Its also "only" 3.3 hours integration (OSC?). I don't know your sky pollution situation but it looks really nice.

 

You will benefit by reducing your stars to bring out more of the nebulosity. Your star field is dominating your image. Maybe you wanted it like that?

 

I didn't see any artifacts that pop out, I can take a closer look later for sure.

 

Regarding different stretch and contrast. This again is your choice. What do you want to emphasize in your image?

Thanks again, Eyal

 

I actually did an EZsuite star reduction.  In the past I have used a star mask and MT with decent results--but EZ again was better and easier.  Obviously I will have to work a little harder :) --it also seemed that with more reduction I get some artifacts--at least I like star fields :)

 

I'm happy that you think the NR looks ok at first glance--but I get the impression that more integration rather than more aggressive NR would be better.

 

Lastly, I think you are steering me in the localized HT and masking areas--I certainly could use some practice at it :)

 

Regards,

 

Brad


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#6 the Elf

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Posted 26 October 2020 - 03:31 PM

Honestly speaking it's a good result given the relative simplicity of the workflow. I put in a considerable amount of fine tuning while trying to maintain your original style and not doing a different interpretation. It is possible to get more detail out but not much.

 

full image at 25% scale:

full.jpg

...

ok, someone got in between in the few seconds between my posts.


Edited by the Elf, 26 October 2020 - 03:38 PM.

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#7 imtl

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Posted 26 October 2020 - 03:32 PM

I'm happy that you think the NR looks ok at first glance--but I get the impression that more integration rather than more aggressive NR would be better.

 

There you go :)

 

Lastly, I think you are steering me in the localized HT and masking areas--I certainly could use some practice at it smile.gif

 

Off you go :)


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#8 the Elf

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Posted 26 October 2020 - 03:32 PM

center crop at 60% size:

crop.jpg


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#9 the Elf

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Posted 26 October 2020 - 03:44 PM

Some users post far larger images that are not scaled down (e.g. here: https://www.cloudyni.../#entry10611866 )

What is the trick to get them so large. In my browser at least.

The scaled versions are just muddy. Not sure if this is a setting at CN or my browser (firefox). When clicked they are razor sharp. Can anyone explain?


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#10 42itous1

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Posted 26 October 2020 - 04:23 PM

Honestly speaking it's a good result given the relative simplicity of the workflow. I put in a considerable amount of fine tuning while trying to maintain your original style and not doing a different interpretation. It is possible to get more detail out but not much.

 

full image at 25% scale:

attachicon.giffull.jpg

...

ok, someone got in between in the few seconds between my posts.

Very Nice Elf !

 

I see that you have made the bubble "pop" out more :)

 

Also, don't know if you may have used Adam B.'s method of star reduction. but you seemed to have reduced the effect of the stars on the object, while keeping them in the image.

 

Your colors are nicer and sharper

 

your processing also makes the image look sort of "softer" in a good way--the stars have a sort of "glow" instead of how blocky mine are.



#11 the Elf

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Posted 27 October 2020 - 02:09 AM

Thank you.

Main steps are

- extract L from the image

- deconvolution of L, arcsinh stretch, HT

- denoise L

- denoise OSC

- arcsinh on OSC

- extract layers

- removes stars from red

- mix L and red for brighter nebula

- add starless red to red with stars to enhance nebula

- combine channels

- combine with L

- extract a residual (wavelets) from R as a mask

- use the mask to individually fine tune background and stars and individually tune the nebula

- copy L, remove large objects, keep stars as a mask

- with that mask on OSC morphologically erode stars

- some color adjustment, some LHE

- minimal unsharp mask with L mask applied

The glow comes from erosion plus unsharp mask

all my methods, never watched any of Block's videos I must admit. Should I?

 

all the best

the Elf

 

PS: finally someone explained to me how to post larger and clear images. Here is my bubble for comparison. Workflow is shown in this video:

https://www.youtube....h?v=OxX1aC6kiwM

 

Bubble_2019_1080.jpg


Edited by the Elf, 27 October 2020 - 02:10 AM.

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